Obtaining from an existing refrigeration machine a representative sample of its refrigerant fluid in the liquid phase, and assaying the sample using refractive index techniques.
The refrigerating cycle which mechanically compresses gaseous refrigerant into the liquid phase, and cools surroundings when the liquid is vaporized is famous and needs no explanation here. Halogenated carbon compounds such as CFC""s, while ideal for refrigerant purposes, have proved to be a profound risk to the environment. For this reason their release into the atmosphere is generally forbidden.
The places the owner of a refrigerant system, especially of large air conditioning systems in a quandary. He can, of course, hire a collection service to remove all of the gases and replace them with others of known composition, but this is an economic cost which should be avoided if possible.
If a complete recharge is to be avoided by adding make-up gas, the question is what kind of gas to add to the system. There are many kinds of refrigerant gases available, and the owner has no reliable way to know what is actually there especially in older systems. It is unwise to mix unknown gases. A device, suitably portable, is needed to learn the constituent gases in the system being serviced.
Systems have been proposed to assay the contents of a system, but have not provided a convenient and sufficiently accurate sample preparation and assaying technique. It is an object to provide such a system and method.
A known system to recover refrigerant gas for later disposal is shown in applicant""s U.S. Pat. No. 6,620,372, issued Jul. 17, 2001. While it can remove the gases, it is not adapted to assay them, and especially not with the use of a refractive index analyzer.
A sampling and assaying system according to this invention receives refrigerant fluid from a machine whose fluid is to be assayed. The fluid is preferably received in its liquid phase. If not, it must be converted to the liquid phase before being analyzed. After the fluid enters this system, it is filtered and de-acidified. Thereafter it passes through an oil separator, another filter, and a drier. At this point, the undesirable contaminants will have been removed. A pump removes the xe2x80x9cpurifiedxe2x80x9d refrigerant, which now may be removed from the system for assay purposes.
According to this invention a refractive index analyzer is disposed between two selector valves, which can be set to permit the liquid to enter the analyzer. Alternatively, they can be set to direct the system fluid to a recovery tank.
Accordingly, this system can be utilized as a collector from the refrigeration machine for disposal elsewhere, or as an analyzer for successive analytical runs.
The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which: